X-Ray Radiation from Tokamaks

Tokamak discharges, which are studied for the magnetic confinement of fusion plasmas, emit soft x-ray radiation in the energy range from 1–20 keV. This radiation consists of a bremsatrahlung and recombination continuum, and characteristic line spectra of impurity ions from the plasma limiter and the walls of the vacuum vessel. The radiation represents a unique source of information and is increasingly used as a diagnostic of plasma parameters. This includes measurements of the electron and ion temperature, investigation of the ionization equilibrium and particle transport, and the study of MHD fluctuations and disruptions.